No abstract

When the ovary of a laying hen contains a mature follicle, ovulation can be induced by an injection of corticosterone. The dose which is required to consistently induce a premature ovulation causes the plasma concentration of corticosterone in the peripheral blood to rise to levels which are higher than those normally observed during the ovulation cycle. The accompanying rise and fall in progesterone which follows an injection of corticosterone. It was concluded that the pituitary gland for both ovulation and progesterone secretion to occur.

No abstract

Individual chorion taken from cows in early pregnancy (days 27, 44, 45 and 49) was incubated with [14C]androstenedione in short-term incubation in vitro. After preliminary extraction, separation and purification, metabolites were identified by recrystallization with authentic unlabelled steroids to constant specific activity. Major metabolites identified were 5 beta-androstane-3,17-dione (5 beta-androstanedione) and 5 beta-androstan-3 alpha-ol-17-one (aetiocholanolone) while minor metabolites were identified as 5 beta-androstane-3 alpha,17 beta-diol and 5 beta-androstan-17 alpha-ol-3-one. There was no 14C-labelled oestradiol or oestradiol detectable in the medium either as free oestrogens or as sulphates.